Expandable Support Frame and Medical Device

ABSTRACT

Support frames and medical devices are described. An example medical device comprises an expandable support frame with first and second leaflets attached to the support frame. Each of the first and second leaflets defines a domed radius that is equal to or less than the radius of the expandable support frame when the expandable support frame is in an expanded configuration and the leaflets are subjected to fluid pressure sufficient to affect closure of the valve orifice.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/804,049, filed on Nov. 6, 2017, which is a continuation of U.S.patent application Ser. No. 14/176,364, filed on Feb. 10, 2014, andwhich claims the benefit of U.S. Provisional Application No. 61/763,107,filed on Feb. 11, 2013. The entire contents of each of these relatedapplications is incorporated into this disclosure by reference.

FIELD

The disclosure relates generally to the field of implantable medicaldevices. More particularly, the disclosure relates to intraluminalsupport frames and medical devices. Particular embodiments relating tointraluminal valve devices and support frames suitable for use in suchdevices are described in detail.

BACKGROUND

Expandable intraluminal support frames have proven useful in the medicalarts. Some expandable support frames are useful without inclusion of anyadditional elements. Stents, for example, are routinely used in severalbody lumens as a means for providing support to ailing vessels, such ascoronary and non-coronary vessels. In some medical devices, anexpandable support frame provides a scaffold onto which one or moreadditional elements can be attached to achieve a desired function.Occlusion devices, for example, often include a graft or othersheet-like material attached to an expandable support frame. Constructedin this way, these medical devices can be delivered and deployedintraluminally to substantially block fluid flow through a body vessel.Similarly, some valve devices include a leaflet or leaflets attached toan expandable support frame in a manner that allows the leaflet orleaflets to move between open and closed positions. Constructed in thisway, these medical devices can be delivered and deployed intraluminallyto regulate fluid flow through a body vessel.

Considering these roles of intraluminal support frames in the medicalarts, a need exists for improved frames. Furthermore, for the varioustypes of intraluminal medical devices that include a support frame andone or more additional elements, a need exists for improved frames thatimprove the effectiveness of the composite device.

Valve devices provide an example. Several researchers have pursued thedevelopment of prosthetic valves that are implantable by minimallyinvasive techniques. Indeed, the art now contains several examples ofimplantable venous valve devices. Many of these prior art devicesinclude an expandable support frame and an attached graft member that isfashioned into a valve that regulates fluid flow through the device and,ultimately, a body vessel. For example, a graft member can be in theform of a leaflet that is attached to a support frame and movablebetween first and second positions. In a first position, the valve isopen and allows fluid flow to proceed through a vessel in a firstdirection, and in a second position the valve is closed to prevent fluidflow in a second, opposite direction. Examples of this type ofprosthetic valve are described in commonly owned U.S. Pat. No. 6,508,833to Pavcnik for a MULTIPLE-SIDED INTRALUMINAL MEDICAL DEVICE, which ishereby incorporated by reference in its entirety.

Despite this and other examples, a need remains for improved medicaldevices, including implantable valve devices, that include an expandablesupport frame.

BRIEF OVERVIEW OF EXAMPLE EMBODIMENTS

Various example support frames and medical devices are described andillustrated herein.

An example support frame comprises a first circumferential serpentinepath; a second circumferential serpentine path; a first connectorsegment joining the first and second serpentine paths, the firstconnector segment comprising substantially parallel first and secondstruts; a second connector segment disposed substantially opposite thefirst connector segment with respect to the longitudinal axis of thesupport frame and joining the first and second serpentine paths, thesecond connector segment comprising substantially parallel third andfourth struts; a third connector segment disposed circumferentiallyadjacent the first and second connector segments and joining the firstand second serpentine paths; a fourth connector segment disposedsubstantially opposite the third connector segment and joining the firstand second serpentine paths; a first connector strut extending betweenand joining the first and third connector segments; and a secondconnector strut extending between and joining the second and thirdconnector segments.

An example medical device comprises an expandable support frame having alongitudinal axis, an outer circumference, an unexpanded configuration,and an expanded configuration with an expanded configuration radiusextending from the longitudinal axis to the outer circumference; a firstleaflet attached to the support frame along a first attachment pathway,the first leaflet having a first inner surface that defines a domedradius equal to or less than the expanded configuration radius when thesupport frame is in the expanded configuration; and a second leafletattached to the support frame along a second attachment pathway, thesecond leaflet having a second inner surface that defines a second domedradius equal to or less than the expanded configuration radius when thesupport frame is in the expanded configuration.

Another example medical device comprises an expandable support framehaving a longitudinal axis, an outer circumference, an unexpandedconfiguration, and an expanded configuration with an expandedconfiguration radius extending from the longitudinal axis to the outercircumference. For this example medical device, the expandable supportframe comprises a first circumferential serpentine path; a secondcircumferential serpentine path; a first connector segment joining thefirst and second serpentine paths, the first connector segmentcomprising substantially parallel first and second struts; a secondconnector segment disposed substantially opposite the first connectorsegment with respect to said longitudinal axis and joining the first andsecond serpentine paths, the second connector segment comprisingsubstantially parallel third and fourth struts; a third connectorsegment disposed circumferentially adjacent the first and secondconnector segments and joining the first and second serpentine paths; afourth connector segment disposed substantially opposite the thirdconnector segment and joining the first and second serpentine paths; afirst connector strut extending between and joining the first and thirdconnector segments; and a second connector strut extending between andjoining the second and third connector segments. This example medicaldevice includes a leaflet attached to the support frame along anattachment pathway extending along the first and second connector strutsand along a portion of the first connector segment and a portion of thesecond connector segment, the leaflet having an inner surface thatdefines a domed radius equal to or less than the expanded configurationradius when the support frame is in the expanded configuration. Thedomed radius can be any suitable domed radius, including a domed radiusthat is between about ⅛^(th) the expanded configuration radius and theexpanded configuration radius, a domed radius that is between about¼^(th) the expanded configuration radius and about ¾^(th) the expandedconfiguration radius, and a domed radius that is about ¼^(th) theexpanded configuration radius.

Another example medical device is similar to the example medical devicedescribed above, but also includes a second leaflet attached to thesupport frame along a second attachment pathway extending along thethird and fourth connector struts and along a portion of the firstconnector segment and a portion of the second connector segment. Similarto the first leaflet, the second leaflet can have a domed radius equalto or less than the expanded configuration radius when the support frameis in the expanded configuration. For the second leaflet, the domedradius can be any suitable domed radius, including a domed radius thatis between about ⅛^(th) the expanded configuration radius and theexpanded configuration radius, a domed radius that is between about¼^(th) the expanded configuration radius and about ¾^(th) the expandedconfiguration radius, and a domed radius that is about ¼^(th) theexpanded configuration radius.

In another example medical device having first and second leaflets, asbriefly described above, the first and second leaflets have domed radiithat are substantially equal. In another example medical device havingfirst and second leaflets, as briefly summarized above, the first andsecond leaflets have domed radii that are equal.

Additional understanding of the inventive support frames and medicaldevices can be obtained with review of the detailed description, below,and the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a first example support frame.

FIG. 2 another perspective view of the first example support frame,rotated ninety degrees from the view illustrated in FIG. 1 .

FIG. 3 is a side view of a second example support frame.

FIG. 4 is another side view of the second example support frame, rotatedninety degrees from the view illustrated in FIG. 3 .

FIG. 5 is a flat plan view of the support frame illustrated in FIGS. 3and 4 .

FIG. 6 is a side view of a third example support frame.

FIG. 6A is a partial side view of an alternate support frame.

FIG. 6B is a partial side view of another alternate support frame.

FIG. 7 is another side view of the third example support frame, rotatedninety degrees from the view illustrated in FIG. 6 .

FIG. 8 is a perspective view of a first example medical device.

FIG. 9 is a side view of a second example medical device.

FIG. 10 is another side view of the second example medical device,rotated ninety degrees from the view illustrated in FIG. 9 .

FIG. 11 is a side view of a third example medical device.

FIG. 12 is another side view of the third example medical device,rotated ninety degrees from the view illustrated in FIG. 11 .

DETAILED DESCRIPTION OF ILLUSTRATED EXAMPLE EMBODIMENTS

The following detailed description and the appended drawings describeand illustrate various example support frames and medical devices thatare embodiments of the invention. The description and drawings areexemplary in nature and are provided to enable one skilled in the art tomake and use one or more support frames or medical devices as anembodiment of the invention. The description and drawings are notintended to limit the scope of the claims in any manner.

Inventive intraluminal support frames and medical devices are described.The support frames are useful in the making of intraluminal medicaldevices, including the medical devices described herein. The supportframes may also be useful as medical devices themselves, such asintraluminal stents. The medical devices can be used in any suitableintraluminal environment and to achieve any desired treatment effect inan animal, including human and non-human animals. For example, some ofthe example medical devices are useful for regulating fluid flow througha body vessel of a patient. As such, the medical devices can be used asvalve devices. The medical devices also may be useful for otherintraluminal purposes.

Support Frames

FIGS. 1 and 2 illustrate a first example support frame 100.

The support frame 100 is an expandable support frame comprising proximal102 and distal 104 portions connected by various connector segments 106,108, 110, 112. The proximal portion 102 defines a first serpentine path114 that extends around the circumference of the support frame 100. Thedistal portion 104 defines a second serpentine path 116 that alsoextends around the circumference of the support frame 100. The firstserpentine path 114 includes pairs of straight strut portions 118 andbends 120, each of which is disposed between and connected to acircumferentially adjacent pair of the connector segments 106, 108, 110,112. The second serpentine path 116 includes curvilinear struts 122,124, 126, 128. Similar to the first serpentine path 114, each of thecurvilinear struts 122, 124, 126, 128 is disposed between and connectedto a circumferentially adjacent pair of the connector segments 106, 108,110, 112. Thus, each serpentine path 114, 116 is joined to connectorsegments 106, 108, 110, 112.

In the illustrated embodiment, each of the connector segments 106, 108,110, 112 includes first and second straight struts, designated by thecorresponding reference number along with a or b, e.g., 110 a, 110 b,that are disposed parallel to each other. For each of the connectorsegments 106, 108, 110, 112, the straight struts are connected to eachother by to curvilinear struts, designated by the correspondingreference number along with c or d, e.g., 110 c, 110 d. This arrangementof struts in the connector segments 106, 108, 110, 112 is consideredadvantageous at least because it provides a degree of structuralredundancy and gives a secondary attachment point for associatedmaterials and/or components in medical devices that include the supportframe 100. In the illustrated embodiment, each of connector segments106, 108, 110, 112 is disposed substantially on the circumferentialplane of the support frame 100. It is noted, though, that one or more ofthe connector segments in a support frame according to a particularembodiment can be disposed entirely or partially outside of thecircumferential plane of the support frame 100. For example, one or moreconnector segments may include a bend or curve that projects outwardlywith respect to a longitudinal axis of the support frame. Connectorsegments with these structural features may be advantageous whenadditional surface area for contact with a wall of a body vessel and/orformation of an artificial sinus is desired, for example.

The support frame 100 illustrated in FIGS. 1 and 2 has four connectorsegments 106, 108, 110, 112. Pairs of these connector segments aredisposed substantially opposite one another with respect to alongitudinal axis a of the support frame 100. Thus, connector segments106 and 108 are disposed substantially opposite each other with respectto longitudinal axis a, and connector segments 110 and 112 are disposedsubstantially opposite each other with respect to longitudinal axis a.As a result, connector segments 106, 108, 110, 112 are distributed onthe circumference of the support frame 100 such that each connectorsegment 106, 108, 110, 112 is positioned approximately equidistantlyfrom two other connector segments 106, 108, 110, 112 along thecircumference. It is noted, though, that, in all embodiments thatinclude more than one connector segment, the connector segments can bedistributed on the circumference of the support frame in any suitablemanner. The illustrated distributions are merely examples of suitabledistributions.

While the support frame 100 illustrated in FIGS. 1 and 2 includes fourconnector segments 106, 108, 110, 112, a support frame according to aparticular embodiment can include any suitable number of connectorsegments. A skilled artisan will be able to determine an appropriatenumber of connector segments for a particular support frame based onvarious considerations, including the nature and size of the body vesselinto which the support frame, or a medical device containing the supportframe, is intended to be implanted and the nature of any materialsand/or additional components that will be attached to the support framein the fabrication of a medical device. When additional rigidity isdesired, a greater number of connector segments can be included. Whenless is desired, one, two or three connector segments can be included.Furthermore, additional or fewer connector segments can be included toaccommodate other materials and/or elements of a medical device in whichthe support frame is used. For example, the use of one, two or threeconnector segments may be advantageous in valve devices in which contactbetween a valve leaflet and a vessel wall is desirable.

In the illustrated embodiment, each of the curvilinear struts 122, 124,126, 128 extends between and joins two of the connector segments 106,108, 110, 112. For example, as best illustrated in FIG. 1 , curvilinearstrut 122 extends between and joins connector segments 106 and 110.Specifically, curvilinear strut 122 is connected to one curvilinearstrut 110 d of connector segment 110 and one curvilinear strut 106 d ofconnector segment 106. Similarly, curvilinear strut 124 extends betweenand joins connector segments 108 and 110. Specifically, curvilinearstrut 124 is connected to one curvilinear strut 110 d of connectorsegment 110 and one curvilinear strut 108 d of connector segment 108. Asbest illustrated in FIG. 2 , curvilinear strut 126 extends between andjoins connector segments 108 and 112. Thus, curvilinear strut 126 isconnected to one curvilinear strut 118 d of connector segment 108 andone curvilinear strut 112 d of connector segment 112. While not visiblein the FIGS., curvilinear strut 128 extends between and joins connectorsegments 112 and 106.

Inclusion of the curvilinear struts at only the distal end 104 of thesupport frame 100 provides directionality to the structure of thesupport frame 100, which is considered advantageous at least because itfacilitates fabrication of medical devices that include the supportframe 100. It is noted, though, that one or more curvilinear struts canbe included on the proximal end, or at any other desirable location, ofa support frame according to a particular embodiment.

Each curvilinear strut 122, 124, 126, 128 can have any suitablecurvilinear configuration. A skilled artisan will be able to determinean appropriate configuration for a support frame according to aparticular embodiment based on various considerations, including thenature of the body vessel within which the support frame is intended tobe used, and the nature, size and configuration of any materials and/oradditional elements that are attached to the support frame in thefabrication of a medical device that includes the support frame.Examples of suitable curvilinear configurations include curvilinearforms that define arcs, circular arcs, great arcs, s-curves, and others.Furthermore, in any particular embodiment, each curvilinear strut, ifmultiple curvilinear struts are included, can have the same or differentcurvilinear configuration as another of the curvilinear struts in thesupport frame. In the illustrated example embodiment, each of thecurvilinear struts has the same curvilinear configuration. Whileconsidered advantageous for this illustrated example, this is merely anexample of a suitable configuration and arrangement.

The inventors have determined that curvilinear struts that definecircular arcs are particularly advantageous for inclusion in the supportframes described herein. For example, each of the curvilinear struts122, 124, 126, 128 in the embodiment illustrated in FIGS. 1 through 2defines a circular arc.

For a curvilinear strut that defines an arc that is a circular arc orgreat arc, the arc can comprise a segment of the circumference of anysuitable circle. As a result, the arc can have any suitable radius ofcurvature. A skilled artisan will be able to select an appropriateradius of curvature for such an arc for a support frame according to aparticular embodiment based on various considerations, such as thenature and size of the body vessel within which the support frame is tobe implanted, the number of curvilinear struts included in the supportframe, and the nature, size and/or configuration of any additionalmaterial or elements included in a medical device within which thesupport frame is used.

The inventors have determined that a radius of curvature that is basedon the radius of the circumference of the support frame in its expandedconfiguration provides desirable structural properties. For thesestructural measurements, the circumference of the support frame is acircumference of a transverse cross-section of the support frame withrespect to the longitudinal axis of the support frame. The radius can bemeasured to either an inner or an outer circumferential surface, or ahypothetical circumferential surface by extension of an actual surface,of the support frame. For example, inclusion of one or more curvilinearstruts that define an arc having a radius of curvature that is betweenabout 1/16^(th) the radius of the circumference of the support frame inits expanded configuration and about 1× the radius of the circumferenceof the support frame in its expanded configuration is suitable.Additional examples of suitable radii of curvature for curvilinearstruts include radii of curvature between about ⅛^(th) the radius of thecircumference of the support frame in its expanded configuration andabout 1× the radius of the circumference of the support frame in itsexpanded configuration is suitable, radii of curvature between about¼^(th) and about ¾^(th) the radius of the circumference of the supportframe in its expanded configuration, and a radius that is about ½ theradius of the circumference of the support frame in its expandedconfiguration.

In the embodiment illustrated in FIGS. 1 and 2 , the support frame 100includes four curvilinear struts 122, 124, 126, 128, each of whichdefines an arc having a radius of curvature r that is about ½ the radiusR of the circumference of the support frame in its expandedconfiguration. The inventors have determined that this configuration andnumber of curvilinear struts 122, 124, 126, 128 is advantageous forinclusion on support frames according to particular embodiments at leastbecause of the beneficial structural properties provided by thearrangement. Furthermore, as described in more detail below, theinventors have determined that this configuration and number ofcurvilinear struts 122, 124, 126, 128 is advantageous for inclusion inmedical devices according to particular embodiments at least because ofthe attachment pathways defined by the curvilinear struts 122, 124, 126,128.

In the illustrated embodiment, support frame 100 includes first 140 andsecond 142 support struts, each of which extends between and isconnected to two of the curvilinear struts 122, 124, 126, 128. Whileconsidered optional, the inclusion of support struts 140, 142 mayprovide desirable structural properties for support frames and/ormedical devices according to particular embodiments. If included, thesupport struts can have any suitable size and configuration. Forexample, the support struts can comprise straight struts or curvilinearstruts. As illustrated in FIGS. 1 and 2 , the support struts 140, 142can comprise parabolic-shaped struts. Also, if included, the supportstruts can extend from the respective curvilinear struts at any suitablelocation on each of the curvilinear struts joined by the support strut.For example, as best illustrated in FIG. 1 , support strut 140 extendsfrom a point proximal to the curve defined by each of the joinedcurvilinear struts 122, 124. The inventors have determined that thispositioning is advantageous at least because it provides desirablestructural properties while not significantly interfering with theattachment pathway defined by the support frame 100 when the supportframe 100 is used within a medical device and an additional materialand/or additional element is attached to the curvilinear struts 122, 124along the attachment pathway, as described below.

In all embodiments, the support frame advantageously comprises anexpandable support frame having radially compressed and radiallyexpanded configurations. Such a support frame can be implanted at apoint of treatment within a body vessel by minimally invasivetechniques, such as delivery and deployment with a catheter sized andconFIG.d for navigation within the body vessel. It is noted, though,that support frames and medical devices according to embodiments of theinvention, regardless of the type and/or nature of the support frame,can be implanted by other techniques, including surgical techniques.

In all embodiments, the support frame can provide a stenting function,i.e., exert a radially outward force on the interior wall of a vessel inwhich the support frame, or medical device including the support frame,is implanted. By including a support frame that exerts such a force, amedical device according to the invention can provide multiplefunctions, such as a stenting and a valving function, at a point oftreatment within a body vessel, which may be desirable in certainsituations, such as when a degree of vessel stenosis, occlusion, and/orweakening is present.

Support frames according to particular embodiments can includeadditional structural elements, such as additional struts and bends. Theinclusion of additional struts and/or bends may be desirable, forexample, in support frames and medical devices intended for implantationat locations in the body where lower radial force on the tissue isdesired. For these embodiments, the inclusion of additional strutsand/or bends can distribute the radial force of the support frame acrossmore structural elements, thereby reducing the radial force exerted by aparticular portion of the support frame against tissue at a point oftreatment. A support frame according to an embodiment can includeconventional structural features that facilitate anchoring of thesupport frame at a point of treatment within a body vessel, such asbarbs and/or microbarbs, and structural features, such as radiopaquemarkers, that facilitate visualization of the support frame inconventional or other medical visualization techniques, such asradiography, fluoroscopy, and other techniques. Furthermore, a supportframe according to an embodiment can include structural features, suchas eyelets, barbs, fillets and other suitable structures, that provideattachment points for grafts and other materials.

In all embodiments, the support frame can be self-expandable or canrequire an input of force to affect expansion, such as a balloonexpandable support frame. Each type of support frame has advantages andfor any given application, one type may be more desirable than othertypes based on a variety of considerations. For example, in theperipheral vasculature, vessels are generally more compliant andtypically experience dramatic changes in their cross-sectional shapeduring routine activity. Support frames and medical devices forimplantation in the peripheral vasculature should retain a degree offlexibility to accommodate these changes of the vasculature.Accordingly, support frames and medical devices according to theinvention intended for implantation in the peripheral vasculature, suchas valve devices, advantageously include a self-expandable supportframe.

In all embodiments, the support frames can be made from any suitablematerial and a skilled artisan will be able to select an appropriatematerial for use in a support frame according to a particular embodimentbased on various considerations, including any desired flexibility andvisualization characteristics. The material selected for a support frameaccording to a particular embodiment need only be biocompatible or beable to be made biocompatible. Examples of suitable materials include,without limitation, stainless steel, nickel titanium (NiTi) alloys,e.g., Nitinol, other shape memory and/or superelastic materials,molybdenum alloys, tantalum alloys, titanium alloys, precious metalalloys, nickel chromium alloys, cobalt chromium alloys, nickel cobaltchromium alloys, nickel cobalt chromium molybdenum alloys, nickeltitanium chromium alloys, linear elastic Nitinol wires, polymericmaterials, and composite materials. Also, absorbable and bioremodellablematerials can be used. As used herein, the term “absorbable” refers tothe ability of a material to degrade and to be absorbed into a tissueand/or body fluid upon contact with the tissue and/or body fluid. Anumber of absorbable materials are known in the art, and any suitableabsorbable material can be used. Examples of suitable types ofabsorbable materials include absorbable homopolymers, copolymers, orblends of absorbable polymers. Specific examples of suitable absorbablematerials include poly-alpha hydroxy acids such as polylactic acid,polylactide, polyglycolic acid (PGA), or polyglycolide; trimethlyenecarbonate; polycaprolactone; poly-beta hydroxy acids such aspolyhydroxybutyrate or polyhydroxyvalerate; or other polymers such aspolyphosphazines, polyorganophosphazines, polyanhydrides,polyesteramides, polyorthoesters, polyethylene oxide, polyester-ethers(e.g., polydioxanone) or polyamino acids (e.g., poly-L-glutamic acid orpoly-L-lysine). There are also a number of naturally derived absorbablepolymers that may be suitable, including modified polysaccharides, suchas cellulose, chitin, and dextran, and modified proteins, such as fibrinand casein.

Stainless steel and nitinol are currently considered desirable materialsfor use in the support frame due at least to their biocompatibility,shapeability, and well-characterized nature. Also, cold drawn cobaltchromium alloys, such as ASTM F562 and ASTM F1058 (commercial examplesof which include MP35N™ and Elgiloy™, both of which are available fromFort Wayne Metals, Fort Wayne, Ind.; MP35N is a registered trademark ofSPS Technologies, Inc. (Jenkintown, Pa., USA); Elgiloy is a registeredtrademark of Combined Metals of Chicago LLC (Elk Grove Village, Ill.,USA)), are currently considered advantageous materials for the supportframes at least because they are non-magnetic materials that providebeneficial magnetic resonance imaging (MRI) compatibility and avoid MRIartifacts typically associated with some other materials, such asstainless steel.

The support frames can be fabricated in any suitable manner and by anysuitable technique. Skilled artisans will be able to select anappropriate manner and/or technique for fabricating a support frameaccording to a particular embodiment based on various considerations,including the nature of the material from which the support frame isbeing fabricated. Examples of suitable techniques include forming thesupport frame from wire, such as by wrapping a suitable wire around asuitable mandrel, by cutting the support frame from a tubular section ofan appropriate material, such as by laser-cutting the support frame froma metal tubular member, and by forming the desired structure of thesupport frame in sheet form, such as by vapor deposition or othersuitable technique, configuring the sheet into tubular form, such as byrolling or other suitable technique, and fixing the support frame intubular form, such as by laser-welding or other suitable technique.

FIGS. 3 through 5 illustrate a second exemplary support frame 200.

The support frame 200 of this embodiment is similar to support frame 100illustrated in FIGS. 1 and 2 and described above, except as detailedbelow. Thus, support frame 200 is an expandable support frame comprisingproximal 202 and distal 204 portions connected by various connectorsegments 206, 208, 210, 212. The proximal portion 202 defines a firstserpentine path 214 that extends around the circumference of the supportframe 200. The distal portion 204 defines a second serpentine path 216that also extends around the circumference of the support frame 200. Thefirst serpentine path 214 includes straight strut portions 218 and bends220. Each serpentine path 214, 216 is joined to connector segments 206,208, 210, 212.

Similar to the first exemplary embodiment, connector segments 206 and208 are disposed substantially opposite each other with respect tolongitudinal axis a₁, and connector segments 210 and 212 are disposedsubstantially opposite each other with respect to longitudinal axis a₁.The support frame 200 includes only two connector segments 210, 212 thateach include first and second struts, designated by the correspondingreference number along with a or b, e.g., 210 a, 210 b. Remainingconnector segments 206, 208 each include only a single strut. Thisconfiguration is considered advantageous for support frames and medicaldevices in which a reduction in the overall amount of surface area ofthe support frame is desirable.

Also, the first 210 a and second 210 b struts of the first connectorsegment 210 are disposed at a slight angle with respect to each otherand longitudinal axis a₁, placing the struts 210 a, 210 b in a skewedarrangement with respect to each other. A parallel or substantiallyparallel arrangement of the struts that comprise a particular connectorsegment is considered advantageous, but a skewed arrangement, such asthe arrangement illustrated in FIG. 3 , can be used if desired. In thisembodiment, the first strut 210 a defines first 250 a and second 250 beyelets. Similarly, the second strut 212 b defines first 252 a andsecond 252 b eyelets. Each of the eyelets 250 a, 250 b, 252 a, 252 b isa ring-shaped structure defining an opening. As best illustrated in FIG.3 , the first eyelets 250 a, 252 a are disposed on the struts 210 a, 210b such that the center of each eyelet 250 a, 252 a is positioned on atransverse axis of the support frame 200 that intersects the connectorsegment 210 at a point that is about ¼^(th) of the height h₁ of theconnector segment 210. The second eyelets 250 b, 252 b are disposed onthe struts 210 a, 210 b such that the center of each eyelet 250 b, 252 bis positioned on a transverse axis of the support frame 200 thatintersects the connector segment 210 at a point that is about ½ of theheight h₁ of the connector segment 210. The inclusion of the eyelets 250a, 250 b, 252 a, 252 b at these positions is considered advantageous atleast because they provide attachment points at these positions formaterials or additional elements included in medical devices thatinclude the support frame 200, which can provide beneficial performancecharacteristics. If included, the eyelets can provide other and/oradditional functional properties, also. For example, one or more eyeletscan provide a structure for engagement by a suitable loading tool forplacing a support frame or medical device within a delivery apparatus,such as a catheter. One or more eyelets can also be included to providea structure for engagement by a suitable tool for withdrawing a supportframe or medical device from a storage chamber, such as a hydrationcontainer within which a medical device is stored.

While the example support frame 200 includes four eyelets 250 a, 250 b,252 a, 252 b, any suitable number of eyelets can be included in asupport frame according to a particular embodiment. Furthermore, theeach of the eyelets included in a support frame according to aparticular embodiment can be placed at any suitable position on theconnector segments for that support frame. Furthermore, the eyelet oreyelet on one straight strut in a connector segment can be positioned atthe same or different position, relative to the height of the respectiveconnector segment, as the eyelet or eyelets on another straight strut ina connector segment. A skilled artisan will be able to select anappropriate number of eyelets, an appropriate position for the eyelet oreyelets on the struts of a connector segment, and the relativedistribution of the eyelet or eyelets on the straight struts of aconnector segment in a support frame according to a particularembodiment based on various considerations, including any desiredattachment points for an additional element, such as a graft or leaflet,that will be attached to the support frame, such as in the making of amedical device.

Also in this embodiment, the support frame 200 includes centering struts244, 246, each of which extends in a proximal and radially outwarddirection from one of the straight strut portions 218 of the firstserpentine path 214. The inventors have determined that the inclusion ofcentering struts 244, 246 provides beneficial deployment and positioningproperties. For example, upon deployment in a body vessel, centeringstruts 244, 246 provide additional contact with the wall of the bodyvessel at the proximal portion 202 of the support frame 200, which canprevent or minimize tilting of the support frame 200 with respect to thelongitudinal axes of the support frame 200 and the body vessel. Ifincluded, the centering struts can have any suitable size andconfiguration. For example, the centering struts can comprise straightstruts, angled struts, a combination of straight struts and bends, as inthe illustrated embodiment, or additional curvilinear struts. Thesestruts, if included, can also provide a desirable location for placementof visualization makers, either as a structure fully or partially formedby these struts or as a structure attached to these struts.

In this embodiment, a series of connector struts 260, 262, 264, 266extend between and join pairs of the connector segments 206, 208, 210,212. Each of the connector struts 260, 262, 264, 266 extends between oneof the connector segments 210, 212 that includes two struts, such asstruts 210 a and 210 b, and one of the connector segments that includesonly a single strut, such as connector segment 208. Thus, for example,connector strut 260 extends between and joins connector segments 210 and206. Similarly, connector strut 262 extends between and joins connectorsegments 210 and 208.

Each of the connector struts 260, 262, 264, 266 lies on a plane that isdisposed at an angle γ to a plane t₁ that orthogonally transects thelongitudinal axis a₁ and includes the terminal structures of the distalportion 204 of the support frame 200. Each connector strut 260, 262,264, 266 can lie on a plane disposed at any suitable angle. A skilledartisan will be able to determine an appropriate angle for eachconnector strut in a support frame according to a particular embodimentbased on various considerations, including the nature of the body vesselwithin which the support frame is intended to be used, and the nature,size and configuration of any materials and/or additional elements thatare attached to the support frame in the fabrication of a medical devicethat includes the support frame. Examples of suitable angles includeangles between about 30° and about 50°, angles between about 30° andabout 40°, and an angle that is about 35°.

While each of the connector struts 260, 262, 264, 266 in the illustratedembodiment is disposed at the same or substantially the same angle γwhen the support frame is in its expanded configuration, differentangles can be used for some or all of the connector struts. Whileconsidered advantageous, the illustrated configuration is merely anexample of a suitable configuration.

FIGS. 6 and 7 illustrate a third example support frame 300.

The support frame 300 of this embodiment is similar to support frame 200illustrated in FIGS. 3 through 5 and described above, except as detailedbelow. Thus, support frame 300 is an expandable support frame comprisingproximal 302 and distal 304 portions connected by various connectorsegments 306, 308, 310, 312. The proximal portion 302 defines a firstserpentine path 314 that extends around the circumference of the supportframe 300. The distal portion 304 defines a second serpentine path 316that also extends around the circumference of the support frame 300. Thefirst serpentine path 314 includes straight strut portions 318 and bends320. Each serpentine path 314, 316 is joined to connector segments 306,308, 310, 312.

Connector segments 306 and 308 are disposed substantially opposite eachother with respect to longitudinal axis a₁, and connector segments 310and 312 are disposed substantially opposite each other with respect tolongitudinal axis a₁. Similar to the embodiment illustrated in FIGS. 3through 5 and illustrated above, the support frame 300 includes only twoconnector segments 310, 312 that each include first and second struts,designated by the corresponding reference number along with a or b,e.g., 310 a, 310 b. Remaining connector segments 306, 308 each includeonly a single strut.

In this embodiment, the pair of struts that define each of connectorsegments 310 and 312 are disposed substantially parallel to each other.Also, each of the struts in the pair of struts that define each ofconnector segments 310 and 312 defines a single eyelet. Thus, as bestillustrated in FIG. 6 , the first strut 310 a of connector segment 310defines eyelet 350 and the second strut 310 b defines eyelet 352. Eachof the eyelets 350, 352 is a ring-shaped structure defining an opening.In this embodiment, each of the eyelets 350, 352 is disposed on therespective strut 310 a, 310 b such that the center of each eyelet 350,352 is positioned on a transverse axis of the support frame 300 thatorthogonally intersects the connector segment 310 at a point that isabout ¼^(th) of the height h₁ of the connector segment 310. It is notedthat, while the illustrated eyelets 350, 352 pass through the entirethickness of the respective struts 310 a, 310 b from one surface to anopposing surface, any other suitable structure can be used, such aspassageways that pass through a partial thickness of the respectivestrut and/or blind openings.

In this embodiment, a series of connector struts 360, 362, 364, 366extend between and join pairs of the connector segments 306, 308, 310,312. Each of the connector struts 360, 362, 364, 366 extends between oneof the connector segments 310, 312 that includes two struts, such asstruts 310 a and 310 b, and one of the connector segments that includesonly a single strut, such as connector segment 308. Thus, for example,connector strut 360 extends between and joins connector segments 310 and306. Similarly, connector strut 362 extends between and joins connectorsegments 310 and 308.

In this embodiment, each of the connector struts 360, 362, 364, 366 is acurvilinear strut that includes a straight portion, designated by thecorresponding reference number along with a. The straight portion 360 a,362 a, 364 a, 366 a of each of the connector struts 360, 362, 364, 366lies on a plane that is disposed at an angle γ to a plane thatorthogonally transects the longitudinal axis a₁ and includes theterminal structures of the distal portion 304 of the support frame 300.Each connector strut 360, 362, 364, 366 can lie on a plane disposed withits respective straight portion 360 a, 362 a, 364 a, 366 a at anysuitable angle. A skilled artisan will be able to determine anappropriate angle for each connector strut in a support frame accordingto a particular embodiment based on various considerations, includingthe nature of the body vessel within which the support frame is intendedto be used, and the nature, size and configuration of any materialsand/or additional elements that are attached to the support frame in thefabrication of a medical device that includes the support frame.Examples of suitable angles include angles between about 30° and about50°, angles between about 30° and about 40°, and an angle that is about35°.

While each of the connector struts 360, 362, 364, 366 in the illustratedembodiment is disposed with the respective straight portion 360 a, 362a, 364 a, 366 a at the same or substantially the same angle γ when thesupport frame is in its expanded configuration, different angles can beused for some or all of the connector struts. While consideredadvantageous, the illustrated configuration is merely an example of asuitable configuration.

Each of FIGS. 6A and 6B illustrate a connector segment 310′ of analternative support frame. In each figure, the connector segment 310′includes alternative structure for the eyelets 350, 352 illustrated inFIG. 6 . In these alternative embodiments, bars 350′, 352′ are includedinstead of the eyelets. The purpose of the bars 350′, 352′ is the sameas the eyelets 350, 352 illustrated in FIG. 6 , but the structure isdifferent. Instead of defining an opening, each bar 350′, 352′ is astraight member or substantially straight member that extends betweenthe pair of struts 310 a′, 310 b′ that define a connector segments 310′.If included in a support frame or medical device according to aparticular embodiment, any suitable number of bars can be included andeach of the included bars can be placed in any suitable position. Ineach of FIGS. 6A and 6B, two bars 350′, 352′ are included, but eachfigure illustrates a different relative positioning for the bars 350′,352′.

If included, the bars 350′, 352′ can be positioned in a similar manneras the eyelets 350, 352 in the support frame 300 illustrated in FIG. 6 .Thus, as illustrated in FIGS. 6A and 6B, one bar 350′ is disposed on therespective struts 310 a′, 310 b′ such that the lengthwise axis of thebar 350′ is positioned on a transverse axis of the support frame 300′that orthogonally intersects the connector segment 310′ at a point thatis about ¼^(th) of the height h₁′ of the connector segment 310′. Thisheight is represented as h₂′ in FIGS. 6A and 6B.

Inclusion of additional bars is optional. If included, any additionalbars can be positioned at any suitable location on the connector segment310′. FIGS. 6A and 6B illustrate example positioning for a second bar352′. In FIG. 6A, a second bar 352′ is disposed on the respective struts310 a′, 310 b′ such that the lengthwise axis of the bar 352′ ispositioned on a transverse axis of the support frame 300′ thatorthogonally intersects the connector segment 310′ at a point that isabout ½ of the height h₁′ of the connector segment 310′. This height isrepresented as h₃′ in FIG. 6A. In this arrangement, the second bar 352′is largely independent of the first bar 350′ and provides a second,independent point of attachment for additional materials, such as avalve leaflet or graft material.

In FIG. 6B, a second bar 352′ is disposed on the respective struts 310a′, 310 b′ such that the bar is associated closely with the first bar350′. In this embodiment, a hypothetical line extending between the pairof struts 310 a′, 310 b′ that define connector segment 310′ and that isspaced equidistantly from each of the bars 350′, 352′ is positioned on atransverse axis of the support frame 300′ that orthogonally intersectsthe connector segment 310′ at a point that is about ¼^(th) of the heighth₁′ of the connector segment 310′. This height is represented as h₂′ inFIGS. 6A and 6B. In this arrangement, the second bar 352′ is paired withthe first bar 350′ to cooperatively define an opening that provides apoint of attachment for additional materials, such as a valve leaflet orgraft material.

Medical Devices

FIG. 8 illustrates a first exemplary medical device 400.

The medical device 400 is a valve device that includes the first examplesupport frame 100 illustrated in FIGS. 1 and 2 and first 480 and second482 leaflets. The first leaflet 480 is attached to the support frame 100along a first attachment pathway 170 that extends along curvilinearstruts 122, 128 and along a portion of connector segments 110, 112.Similarly, the second leaflet 482 is attached to the support frame 100along a second attachment pathway 172 that extends along curvilinearstruts 124, 126 and along a portion of connector segments 110, 112. Eachleaflet 480, 482 has a free edge 484, 486 that is not attached to thesupport frame 100. The free edges 484, 486 cooperatively define valveorifice 488.

The medical device 400 is a valve device that is useful for regulatingfluid flow through a body vessel. Each of the leaflets 480, 482 ismovable between first and second positions. In the first position, theorifice 488 is open and allows fluid flow through the device 400 in afirst direction. In the second position, the free edges 484, 486 ofleaflets 480, 482 come together to close the orifice 488 andsubstantially prevent fluid flow through the device 400 in a second,opposite direction.

Each of the leaflets 480, 482 can have any suitable size, shape and/orconfiguration. A skilled artisan will be able to select leaflets havingappropriate size, shape and configuration properties for a medicaldevice according to a particular embodiment based on variousconsiderations, including any desired performance characteristics of themedical device. The inventors have determined that leaflets that, whenattached to a support frame and when the support frame is in an expandedconfiguration and the leaflets subjected to fluid pressure sufficient toeffect closure of the valve orifice, define a domed radius of curvature,i.e., a portion of one surface of the leaflet lies on a portion of aspherical plane or substantially spherical plane, provide desirableperformance characteristics for medical devices intended to be used asvalve devices, such as prosthetic venous valve devices. In theseembodiments, the portion of a spherical plane or substantially sphericalplane can comprise a portion of the spherical plane of any suitablesphere. As a result, the portion of a spherical plane or substantiallyspherical plane can have any suitable radius of curvature. Also in theseembodiments, the portion the surface of the leaflet that defines thedomed radius can comprise any suitable portion of the leaflet surface,including a central portion that does not contact any struts or otherstructural members of the associated support frame, a base portion thatis positioned at the bottom of a valve pocket formed in the valve devicewhen the valve orifice is closed, or any other suitable portion of theleaflet surface. A skilled artisan will be able to select an appropriateportion of the leaflet surface and an appropriate radius of curvaturefor a medical device according to a particular embodiment based onvarious considerations, including the nature and size of the body vesselwithin which the medical device is to be implanted, and the nature ofthe material from which the leaflets are formed. Also, it is noted thatthe domed radii described herein are present in the respective leafletat least when the leaflet is subjected to fluid pressure sufficient toclose the associated valve orifice, such as when the medical devicecontaining the leaflet is exposed to such fluid pressure in vivo or insuitable testing environments, such as in a vessel simulator or a simplefluid container.

The inventors have determined that leaflets defining a domed radius thatis based on the radius of the circumference of the support frame in itsexpanded configuration provides desirable structural properties. Forexample, inclusion of one or more curvilinear leaflets that define adomed radius having a radius of curvature that is between about ⅛^(th)the radius of the circumference of the support frame in its expandedconfiguration and about 1× the radius of the circumference of thesupport frame in its expanded configuration is suitable. Additionalexamples of suitable radii of curvature include radii of curvaturebetween about ¼^(th) and about ¾^(th) the radius of the circumference ofthe support frame in its expanded configuration, and a radius that isabout ½ the radius of the circumference of the support frame in itsexpanded configuration.

The exemplary medical device 400 is illustrated with the support frame100 in an expanded configuration and with the leaflets 480, 482 in theconfiguration they adopt when subjected to fluid pressure sufficient toeffect closure of the valve orifice. As illustrated in the FIG., in thisstate, each of the leaflets 480, 482 defines a domed radius of curvaturer that is about ½ the radius R of the circumference of the support frame100 in its expanded configuration. The inventors have determined thatthis configuration of the leaflets 480, 482 is advantageous at leastbecause of the beneficial performance characteristics provided by thearrangement.

It is noted that, while the medical device 400 is illustrated asincluding support frame 100, any suitable support frame that positionsthe leaflets 480, 482 in the desired configuration, i.e., with the domedradius, can be used. For example, leaflets can be attached to any of thesupport frame described and illustrated herein such that the desiredconfiguration is achieved. A skilled artisan will be able to select anappropriate support frame for a medical device according to a particularembodiment based on various considerations, including the nature, sizeand configuration of the material forming the leaflets.

FIGS. 9 and 10 illustrate a second example medical device 500.

The medical device 500 is a valve device that includes the thirdexemplary support frame 300 illustrated in FIGS. 6 and 7 and first 580and second 582 leaflets. The first leaflet 580 is attached to thesupport frame 300 along a first attachment pathway 370 that extendsalong connector struts 360, 366 and along a portion of connectorsegments 310, 312. Similarly, the second leaflet 582 is attached to thesupport frame 300 along a second attachment pathway 372 that extendsalong connector struts 362, 364 and along a portion of connectorsegments 310, 312. Each leaflet 580, 582 has a free edge 584, 586 thatis not attached to the support frame 300. The free edges 584, 586cooperatively define valve orifice 588.

The medical device 500 is a valve device that is useful for regulatingfluid flow through a body vessel. Each of the leaflets 580, 582 ismovable between first and second positions. In the first position, theorifice 588 is open and allows fluid flow through the device 500 in afirst direction. In the second position, the free edges 584, 586 ofleaflets 580, 582 come together to close the orifice 588 andsubstantially prevent fluid flow through the device 500 in a second,opposite direction.

In this embodiment, each attachment pathway 370, 372 extends along aportion of the axial length of connector segment 310 and along a portionof the axial length of connector segment 312. For each attachmentpathway 370, 372 and each connector segment 310, 312, the portion of theaxial length of the connector segment 310, 312 along which theattachment pathway extends can be any suitable portion of the axiallength of the connector segment 310, 312, including the entire axiallength of the connector segment 310, 312. For each attachment pathwayand each connector segment in a medical device according to a particularembodiment, a skilled artisan will be able to select an appropriateportion of the axial length along which the attachment pathway extendsbased on various considerations, such as the nature, size andconfiguration of the leaflets or other material and/or additionalelements included in the medical device.

The inventors have determined that a portion of the axial length of theconnector segment along which the attachment pathway extends that isbetween about 1/16^(th) the full axial length of the connector segmentand about the full axial length of the connector segment is suitable.Additional examples of suitable portions of the axial length of theconnector segments along which the attachment pathways extend includeportions of the axial length of the connector segments that are betweenabout ⅛^(th) the full axial length of the connector segment and about¾^(th) the full axial length of the connector segment, and portions ofthe axial length of the connector segments that are between about ¼^(th)the full axial length of the connector segment and about ½ the fullaxial length of the connector segment.

In the embodiment illustrated in FIGS. 9 and 10 , each of the attachmentpathways 370, 372 extends along a portion of each connector segment 310,312 that is equal to about ¼^(th) the full axial length of therespective connector segment 310, 312. In this embodiment, the connectorsegments 310, 312 have approximately equal axial lengths, so theportions of the axial lengths along which the attachment pathways 370,372 extend are also approximately equal. The inventors have determinedthat this configuration of the attachment pathways 370, 372 isadvantageous for inclusion in medical devices according to particularembodiments at least because it provides desirable performancecharacteristics.

In any particular embodiment, the attachment pathways, if included, canextend along the same or different portion of the axial length of eachconnector segment. For example, a medical device according to anembodiment can include a first attachment pathway that extends alongapproximately equal portions of the axial lengths of first and secondconnector segments and a second attachment pathway that extends alongapproximately equal portions of the axial lengths of the first andsecond connector segments that are different than the portions alongwhich the first attachment pathway extends. Furthermore, a medicaldevice according to an embodiment may include one or more attachmentpathways that extends along a portion of the axial length of a firstconnector segment and along a portion of the axial length of a secondconnector segment that is less than, equal to, approximately equal to,or greater than the portion of the axial length of the first connectorsegment.

In the illustrated embodiment, the attachment pathways 370, 372 alsoextend along connector struts 360, 362, 364, 366 that extend between andjoin adjacent pairs of connector segments 306, 308, 310, 312. Ifincluded, any suitable connector struts can be used in a medical deviceaccording to a particular embodiment and a skilled artisan will be ableto select appropriate connector struts based on various considerations,including the nature of the material from which the element(s) beingattached to the support frame, such as leaflets, is formed. Asillustrated in FIGS. 9 and 10 , connector struts 360, 362, 364, 366 thateach comprise a curvilinear strut that includes a straight portion,designated by the corresponding reference number along with a, areconsidered suitable. In the illustrated embodiment, the straight portion360 a, 362 a, 364 a, 366 a of each of the connector struts 360, 362,364, 366 lies on a plane that is disposed at an angle γ₂ to a plane thatorthogonally transects the longitudinal axis a₄ and includes theterminal structures of the distal portion 304 of the support frame 300.Each connector strut 360, 362, 364, 366 can be disposed with itsrespective straight portion 360 a, 362 a, 364 a, 366 a at any suitableangle. A skilled artisan will be able to determine an appropriate anglefor each connector strut in a support frame according to a particularembodiment based on various considerations, including the nature of thebody vessel within which the support frame is intended to be used, andthe nature, size and configuration of any materials and/or additionalelements that are attached to the support frame in the fabrication of amedical device that includes the support frame. Examples of suitableangles include angles between about 30° and about 50°, angles betweenabout 30° and about 40°, and an angle that is about 35°.

FIGS. 11 and 12 illustrate a third example medical device 600.

The medical device 600 is a valve device that includes a modifiedversion of the third exemplary support frame 300′ illustrated in FIGS. 6and 7 and first 680 and second 682 leaflets. The medical device 600 issimilar to the second exemplary medical device 500 described above andillustrated in FIGS. 9 and 10 , except as detailed below. The firstleaflet 680 is attached to the support frame 300′ along a firstattachment pathway 370′ that extends along connector struts 360, 366 andalong a portion of connector segments 310′, 312′. Similarly, the secondleaflet 682 is attached to the support frame 300′ along a secondattachment pathway 372′ that extends along connector struts 362, 364 andalong a portion of connector segments 310′, 312′. Each leaflet 680, 682has a free edge 684, 686 that is not attached to the support frame 300.The free edges 684, 686 cooperatively define valve orifice 688.

The medical device 600 is a valve device that is useful for regulatingfluid flow through a body vessel. Each of the leaflets 680, 682 ismovable between first and second positions. In the first position, theorifice 688 is open and allows fluid flow through the device 600 in afirst direction. In the second position, the free edges 684, 686 ofleaflets 680, 682 come together to close the orifice 688 andsubstantially prevent fluid flow through the device 600 in a second,opposite direction.

In this embodiment, support frame 300 includes eyelets 350′, 352′, 354′,356′. The first 310 a′ strut of the first connector segment 310′ defineseyelet 350′. Similarly, the second strut 310 b′ of the first connectorsegment 310′ defines eyelet 354′. Similarly, the first 312 a′ and second312 b′ struts of the second connector segment each defines one ofremaining eyelets 354′, 356′. Each of the eyelets is a ring-shapedstructure defining an opening. As best illustrated in FIG. 11 , each ofthe 350′, 352′, 354′, 356′ is disposed on the respective strut 310 a′,310 b′, 312 a′, 312 b′ of the respective connector segment 310′, 312′such that the center of each eyelet 350′, 352′, 354′, 356′ is positionedon a transverse axis of the support frame 300′ that intersects theconnector segments 310′, 312′ at a point corresponding to a height h₄that is about ½ of the height h₅ of the respective connector segment310′, 312′. The inclusion of the eyelets 350′, 352′, 354′, 356′ at thesepositions is considered advantageous at least because they provideattachment points at these positions for the leaflets 680, 682, whichcan provide beneficial performance characteristics.

In this embodiment, the free edge 684, 686 of each leaflet defines acurve. If leaflets having this structure are included, any suitablecurve can be used and a skilled artisan will be able to select anappropriate curve or curves based on various considerations, includingthe nature of the material from which the leaflets are formed. As bestillustrated in FIG. 12 , a parabolic curve is considered suitable.Indeed, the inventors have determined that a parabolic curve that, whenthe respective leaflet 682 is attached to the support frame 300, extendsinwardly from points 690, 692 on the respective attachment pathway 372that correspond to a height h₄ is about ½ of the height h₅ of therespective connector segment 312′ to an apex 694 that is at a point thatcorresponds to a height h₆ that is about ¼th of the height h₅ of therespective connector segment 312′, is considered suitable.

If a leaflet having a free edge defining a curve is used, the curve canbe formed prior to attaching the leaflet to the support frame, or can beformed following attachment of the leaflet to the support frame, such asby cutting the leaflet to create a free edge defining a desired curve.

In all embodiments, any suitable materials and/or additional elementscan be attached to the support frame to form a medical device. A skilledartisan will be able to select an appropriate material for use with asupport frame in a medical device according to a particular embodimentbased on various considerations, including the intended use and desiredfunction of the medical device. For valve devices, such as the valvedevice illustrated in FIGS. 9 and 10 , each of the leaflets 580, 582comprises a section of material, such as a sheet, that is attached tothe support frame 300 along a respective attachment pathway 370, 372, asdescribed above. The leaflets 580, 582 can be formed of any suitablematerial, and need only be biocompatible or be able to be madebiocompatible. The material can advantageously be formed of a flexiblematerial. Examples of suitable materials for use as leaflets in medicaldevices that comprise valve devices include natural materials, syntheticmaterials, and combinations of natural and synthetic materials. Examplesof suitable natural materials include extracellular matrix (ECM)materials, such as small intestine submucosa (SIS), and otherbioremodelable materials, such as bovine pericardium. Other examples ofsuitable ECM materials that can be used include stomach submucosa, liverbasement membrane, urinary bladder submucosa, tissue mucosa, and duramater. Other examples of suitable natural materials include renalcapsule matrix, abdominal fascia, parenchyma, such as abdominalparenchyma, connective tissue, pulmonary or lung ligament, tissuelaminates, and natural valve leaflets with or without adjacent vesselwall. Pleura is also considered a suitable natural material, includingvisceral pleura. Fixed tissues are also considered suitable, includingfixed SIS, fixed pericardium, fixed pulmonary or lung ligament, and anyother suitable fixed natural tissue. When fixed tissue is used, anysuitable fixation technique and/or procedure can be used, includingchemical fixatives, such as aldehydes, e.g., formaldehyde,gluteraldehyde, and formalin, and carbodiimides, such as ethyldimethylaminopropyl carbodiimide, dicyclohexylcarbodiimide. Physicalfixation techniques and/or procedures can also be used, includingexposure to heat and/or radiation. Lyophilized preparations andchemically-dried preparations of these natural materials are alsoconsidered suitable. Examples of suitable synthetic materials includepolymeric materials, such as expanded polytetrafluoroethylene,polyurethane, polyurethane urea, polycarbonate, and polyesters.

Any attached materials can have any suitable size, shape andconfiguration. For example, valve devices can include one, two or moreleaflets that are sheet-like sections of material attached to a supportframe according to an embodiment. Another example of a material that canbe attached to a support frame according to an embodiment is a tubularstructure that is attached around the outer circumference of the supportframe. Indeed, a tubular structure and one, two or more leaflets can beattached to a support frame according to an embodiment to form a valvedevice having an outer sleeve.

In all embodiments including additional material and/or elementsattached to the support frame, the additional material and/or elementscan be attached to the support frame in any suitable manner and with anysuitable structure and/or substance. For example, leaflets can beattached to a support frame in a valve device using sutures, tissuewelding, adhesive(s), mechanical attachment(s), a combination of theseapproaches, and any other suitable structure and/or substance.

In all embodiments including an additional material and/or elementsattached to the support frame, the additional material and/or elementscan be attached to the support frame in any suitable orientation. Askilled artisan will be able to select a suitable orientation for aparticular material or element attached to the support frame in aspecific embodiment based on various considerations, including thephysical properties of the material or element and any desiredproperties of the resulting medical device that may be impacted by theorientation of the material or element. For example, for valve devicesthat include one or more leaflets attached to the support frame, it maybe desirable to attach the leaflet or leaflets in a particularorientation based on the ability of the leaflet to stretch in aparticular direction. Anisotropic materials may be able to stretch to agreater degree along one axis than along another axis. The inventorshave determined that, when attaching an anisotropic material to asupport frame to form a medical device, it may be desirable to attachthe material in an orientation in which the axis along which thematerial has a greater ability to stretch is aligned with thelongitudinal axis of the support frame if it is desirable to have theleaflet of the medical device form a relatively deeper valve pocket whenthe medical device is subjected to sufficient fluid pressure to move theleaflet to a closed position. Conversely, the inventors have determinedthat it may be desirable to attach the material in an orientation inwhich the axis along which the material has a greater ability to stretchis aligned in a transverse orientation to the longitudinal axis of thesupport frame if it is desirable to have the leaflet of the medicaldevice form a relatively larger valve orifice when the medical device issubjected to sufficient fluid pressure to move the leaflet to an openposition.

For valve devices, the inventors have determined that attaching aleaflet to a support frame described herein while the leaflet is held inan open position can provide desirable performance characteristics tothe resulting valve device. Specifically, the inventors have determinedthat attaching a leaflet to a support frame described herein while theleaflet is held in an open position on a mandrel such that a degree ofslack is provided in a portion of the leaflet that will have a domedradius can provide desirable performance characteristics to theresulting valve device.

Furthermore, while the medical devices described and illustrated hereinare valve devices, it is noted that other types of medical devices canbe made in accordance with the disclosure. For example, a vesseloccluder can include a support frame according to an embodiment alongwith leaflets that are sewn or otherwise attached to each other topermanently close an associated valve orifice or a graft material thatlacks an orifice.

The support frames and medical devices can be implanted within a bodyvessel at a desired point of treatment using conventionalminimally-invasive techniques, such as by delivery with an associatedcatheter, by surgical techniques, or by any other suitable technique forplacing a support frame or medical device at a point of treatment withina body vessel.

The foregoing detailed description refers to example support frames andmedical devices and includes the best mode for practicing the invention.The description and the appended drawings illustrating the describeddevices are intended only to provide examples and not to limit the scopeof the claims in any manner.

What is claimed is:
 1. A medical device for regulating fluid flowthrough a body vessel of a patient, comprising: an expandable supportframe having a longitudinal axis, an outer circumference, an unexpandedconfiguration, and an expanded configuration, the support framecomprising: a proximal portion, a distal portion, a first connectorsegment, a second connector segment, a third connector segment, and afourth connector segment, the proximal portion and the distal portionconnected by the first, second, third, and fourth connector segments;the proximal portion defining a first circumferential serpentine pathjoined to the first, second, third, and fourth connector segments; thedistal portion defining a second circumferential serpentine path joinedto the first, second, third, and fourth connector segments andcomprising a first connector strut extending between and joining thefirst and third connector segments, a second connector strut extendingbetween and joining the second and third connector segments, a thirdconnector strut extending between and joining the first and fourthconnector segments, and a fourth connector strut extending between andjoining the second and fourth connector segments; the first connectorsegment having an axial length and comprising first and second strutsand a first connecting bar extending between and joining the first andsecond struts, the first connecting bar positioned on a first transverseaxis of the support frame that orthogonally intersects the firstconnector segment at a point between the distal portion and about ½ theaxial length of the first connector segment; the second connectorsegment disposed substantially opposite the first connector segment withrespect to the longitudinal axis, the second connector segmentcomprising third and fourth struts and a second connecting bar extendingbetween and joining the third and fourth struts; the third connectorsegment disposed circumferentially adjacent the first and secondconnector segments, the third connector segment being only a singlestrut; and the fourth connector segment disposed substantially oppositethe third connector segment with respect to the longitudinal axis; afirst leaflet attached to the support frame along an attachment pathwayextending along the first and second connector struts and along a firstportion of the first connector segment extending from the distal portionand toward the proximal portion and a first portion of the secondconnector segment extending from the distal portion and toward theproximal portion, the first leaflet having a first free edge; and asecond leaflet attached to the support frame along a second attachmentpathway extending along the third and fourth connector struts and alonga second portion of the first connector segment and a second portion ofthe second connector segment, the second leaflet having a second freeedge; wherein the first and second free edges cooperatively define avalve orifice.
 2. The medical device of claim 1, wherein the firsttransverse axis of the support frame orthogonally intersects the firstconnector segment at a point that is about ¼^(th) the axial length ofthe first connector segment.
 3. The medical device of claim 1, whereinthe second connector segment has an axial length; and wherein the secondconnecting bar is positioned on a second transverse axis of the supportframe that orthogonally intersects the second connector segment at apoint between the distal portion and about ½ the axial length of thesecond connector segment.
 4. The medical device of claim 3, wherein thesecond transverse axis of the support frame orthogonally intersects thesecond connector segment at a point that is about ¼^(th) the axiallength of the second connector segment.
 5. The medical device of claim1, wherein the first connector segment has a third connecting barextending between and joining the first and second struts.
 6. Themedical device of claim 5, wherein the third connecting bar ispositioned on a third transverse axis of the support frame thatorthogonally intersects the first connector segment at a point betweenthe first connecting bar and the proximal portion.
 7. The medical deviceof claim 5, wherein the second connector segment has a fourth connectingbar extending between and joining the third and fourth struts.
 8. Themedical device of claim 7, wherein the second connector segment has anaxial length; wherein the second connecting bar is positioned on asecond transverse axis of the support frame that orthogonally intersectsthe second connector segment at a point between the distal portion andabout ½ the axial length of the second connector segment; and whereinthe fourth connecting bar is positioned on a fourth transverse axis ofthe support frame that orthogonally intersects the second connectorsegment at a point between the second connecting bar and the proximalportion.
 9. The medical device of claim 1, wherein the first and secondstruts of the first connector segment are substantially parallel; andwherein the third and fourth struts of the second connector segment aresubstantially parallel.
 10. The medical device of claim 1, wherein thefourth connector segment is only a single strut.
 11. The medical deviceof claim 1, wherein each of the first connector strut, the secondconnector strut, the third connector strut, and the fourth connectorstrut comprise a curvilinear strut that includes a straight portion. 12.The medical device of claim 11, wherein the distal portion includesterminal structures; and wherein each of the first connector strut, thesecond connector strut, the third connector strut, and the fourthconnector strut lies on a first plane that is disposed at an angle to asecond plane that orthogonally transects the longitudinal axis andincludes the terminal structures.
 13. The medical device of claim 12,wherein the angle is between about 30° and about 50°.
 14. The medicaldevice of claim 12, wherein the angle is about 35°.
 15. The medicaldevice of claim 1, wherein the first portion of the first connectorsegment is between about ⅛^(th) and about ¾^(th) the axial length of thefirst connector segment; wherein the second connector segment has anaxial length; and wherein the first portion of the second connectorsegment is between about ⅛^(th) and about ¾^(th) the axial length of thesecond connector segment.
 16. The medical device of claim 1, wherein thefirst portion of the first connector segment is about ¼^(th) the axiallength of the first connector segment; wherein the second connectorsegment has an axial length; and wherein the first portion of the secondconnector segment is about ¼^(th) the axial length of the secondconnector segment.
 17. The medical device of claim 1, wherein thesupport frame is free of additional struts between the first connectorsegment and the third connector segment; wherein the support frame isfree of additional struts between the second connector segment and thethird connector segment; wherein the support frame is free of additionalstruts between the first connector segment and the fourth connectorsegment; and wherein the support frame is free of additional strutsbetween the second connector segment and the fourth connector segment.18. The medical device of claim 1, wherein the first and second leafletscomprise a natural material.
 19. A medical device for regulating fluidflow through a body vessel of a patient, comprising: an expandablesupport frame having a longitudinal axis, an outer circumference, anunexpanded configuration, and an expanded configuration, the supportframe comprising: a proximal portion, a distal portion, a firstconnector segment, a second connector segment, a third connectorsegment, and a fourth connector segment, the proximal portion and thedistal portion connected by the first, second, third, and fourthconnector segments; the proximal portion defining a firstcircumferential serpentine path joined to the first, second, third, andfourth connector segments; the distal portion defining a secondcircumferential serpentine path joined to the first, second, third, andfourth connector segments and comprising a first connector strutextending between and joining the first and third connector segments, asecond connector strut extending between and joining the second andthird connector segments, a third connector strut extending between andjoining the first and fourth connector segments, and a fourth connectorstrut extending between and joining the second and fourth connectorsegments; the first connector segment having an axial length andcomprising first and second struts and first and second connecting bars,each of the first and second connecting bars extending between andjoining the first and second struts, the first connecting bar positionedon a first transverse axis of the support frame that orthogonallyintersects the first connector segment at a point between the distalportion and about ½ the axial length of the first connector segment, thesecond connecting bar positioned on a second transverse axis of thesupport frame that orthogonally intersects the first connector segmentat a point between the first connecting bar and the proximal portion;the second connector segment having an axial length and disposedsubstantially opposite the first connector segment with respect to thelongitudinal axis, the second connector segment comprising third andfourth struts and third and fourth connecting bars, each of the thirdand fourth connecting bars extending between and joining the third andfourth struts, the third connecting bar positioned on a third transverseaxis of the support frame that orthogonally intersects the secondconnector segment at a point between the distal portion and about ½ theaxial length of the second connector segment, the fourth connecting barpositioned on a fourth transverse axis of the support frame thatorthogonally intersects the second connector segment at a point betweenthe third connecting bar and the proximal portion; the third connectorsegment disposed circumferentially adjacent the first and secondconnector segments, the third connector segment being only a singlestrut; and the fourth connector segment disposed substantially oppositethe third connector segment with respect to the longitudinal axis; afirst leaflet attached to the support frame along an attachment pathwayextending along the first and second connector struts and along a firstportion of the first connector segment extending from the distal portionand toward the proximal portion and a first portion of the secondconnector segment extending from the distal portion and toward theproximal portion, the first leaflet having a first free edge; and asecond leaflet attached to the support frame along a second attachmentpathway extending along the third and fourth connector struts and alonga second portion of the first connector segment and a second portion ofthe second connector segment, the second leaflet having a second freeedge; wherein the first and second free edges cooperatively define avalve orifice.
 20. A medical device for regulating fluid flow through abody vessel of a patient, comprising: an expandable support frame havinga longitudinal axis, an outer circumference, an unexpandedconfiguration, and an expanded configuration, the support framecomprising: a proximal portion, a distal portion, a first connectorsegment, a second connector segment, a third connector segment, and afourth connector segment, the proximal portion and the distal portionconnected by the first, second, third, and fourth connector segments;the proximal portion defining a first circumferential serpentine pathjoined to the first, second, third, and fourth connector segments; thedistal portion defining a second circumferential serpentine path joinedto the first, second, third, and fourth connector segments andcomprising a first connector strut extending between and joining thefirst and third connector segments, a second connector strut extendingbetween and joining the second and third connector segments, a thirdconnector strut extending between and joining the first and fourthconnector segments, and a fourth connector strut extending between andjoining the second and fourth connector segments; the first connectorsegment having an axial length and comprising first and secondsubstantially parallel struts and first and second connecting bars, eachof the first and second connecting bars extending between and joiningthe first and second struts, the first connecting bar positioned on afirst transverse axis of the support frame that orthogonally intersectsthe first connector segment at a point between the distal portion andabout ½ the axial length of the first connector segment, the secondconnecting bar positioned on a second transverse axis of the supportframe that orthogonally intersects the first connector segment at apoint between the first connecting bar and the proximal portion; thesecond connector segment having an axial length and disposedsubstantially opposite the first connector segment with respect to thelongitudinal axis, the second connector segment comprising third andfourth substantially parallel struts and third and fourth connectingbars, each of the third and fourth connecting bars extending between andjoining the third and fourth struts, the third connecting bar positionedon a third transverse axis of the support frame that orthogonallyintersects the second connector segment at a point between the distalportion and about ½ the axial length of the second connector segment,the fourth connecting bar positioned on a fourth transverse axis of thesupport frame that orthogonally intersects the second connector segmentat a point between the third connecting bar and the proximal portion;the third connector segment disposed circumferentially adjacent thefirst and second connector segments, the third connector segment beingonly a single strut; and the fourth connector segment disposedsubstantially opposite the third connector segment with respect to thelongitudinal axis, the fourth connector segment being only a singlestrut; a first leaflet attached to the support frame along an attachmentpathway extending along the first and second connector struts and alonga first portion of the first connector segment extending from the distalportion and toward the proximal portion and a first portion of thesecond connector segment extending from the distal portion and towardthe proximal portion, the first leaflet having a first free edge; and asecond leaflet attached to the support frame along a second attachmentpathway extending along the third and fourth connector struts and alonga second portion of the first connector segment and a second portion ofthe second connector segment, the second leaflet having a second freeedge; wherein the first and second free edges cooperatively define avalve orifice.